Centrifugal spraying equipment



Oct. 1 8, 1966 .1.v. cLANcY ETAL 3,279,427

CENTRIFUGAL SPRAYING EQUIPMENT Filed Deo. 20, 1965 '7 Sheets-Sheet lATTORNEYS Oct. 18, 1966 J. v. cLANcY ETAL 3,279,427

CENTRIFUGAL SPRAYING EQUIPMENT Filed DSC. 20, 1963 '7 Sheets-Sheet 2 l 4JV ff x L ff J7 M y BYMMM, www

ATTORNEYS Oct' 18, 1966 .1.v. cLANcY ETAL 3,279,427

CENTRIFUGAL SPRAYING EQUIPMENT '7 Sheets-Sheet Z3 Filed Dec. 20, 1963ATTORNEY5 Oct 18, 1966 J, v. cLANcY ETAL 3,279,427

CENTRIFUGL SPRAYING EQUIPMENT Filed Dec. 20, 1963 7 Sheets-Sheet 4 AHL]/z W) lll INVENTORS j/wv FJZQ/vw/ BMM@ @www ATTORNEYS' CENTRIFUGALSPRAYING EQUIPMENT Filed Dec. 20, 1963 7 Sheets-Sheet 5 L #www BY/MMW,@M7 9! www ATTORNEYS Oct. 18, 1966 J. v. cLANcY ETAL 3,279,427

CENTRIFUGAL SPRAYING EQUIPMENT Filed Deo. 20, 1963 7 Sheets-Sheet 6ATTORNEY Oct. 18, 1966 J. v` cLANcY ETAL 3,279,427

CENTRIFUGAL SPRAYING EQUIPMENT Filed Dec. 20, 1963 7 Sheets-Sheet 7,Hfs/N P/rcy/ 5%/ INVENTORS ATTORNEYS United States Patent O ice3,279,427 CENTRIFUGAL SPRAYING EQUIPMENT John V. Clancy and William T.McLaughlin, Pittsburgh, Pa., assignors, by mesne assignments, to UnitedStates Steel Corporation, a corporation of Delaware Filed Dec. 20, 1963,Ser. No. 332,229 19 Claims. (Cl. 118-317) This application is acontinuation-in-part of application Serial No. 330,416, filed December13, 1963.

This invention relates to the preparation of an integral facing orbarrier on the interior surface of concrete pipes, but especially toapparatus for effecting such facing.

Concrete pipes are frequently subjected to service conditions whichcause attack on the inner surface of the pipe. Thus, hydrogen sulfide(and sulfuric .acid formed therefrom) and other agents are released fromwater and sewage carried by such pipes. As a consequence, the art hasturned to vitrified clay in place of concrete in making hydrogen sulfideresistant pipes. Unfortunately, vitrified clay is relatively expensiveand does not have as good structural properties as desired, e.g., itscompressive strength is not as .high as desired.

Concrete pipes further suffer from the disadvantage of having rough,porous interior surfaces and of having inadequate abrasion resistance.

It is an object of the present invention to provide apparatus foreffecting a continuous, integral facing or barrier for the interiorsurface of concrete pipe.

Another object is to provide such apparatus to prepare such a facing orbarrier which is resistant to physical and/ or chemical agents whichattack concrete itself either by corrosion or erosion.

A further object is to provide economical apparatus for applying aprotective facing or barrier to the interior surface of wet or greenconcrete pipe.

An additional object is to provide apparatus for effecting an integralfacing for the interior surface of concrete pipe to provide a productgiving at least `as good protection against hydrogen sulfide andsulfuric acid as vitrified clay and which gives a product structurallysuperior to vitrified clay, e.g., it has better compressive strength.

Yet another object is to provide apparatus for imparting an abrasionresistant, non-porous, smooth facing to the interior surface of concretepipe.

Still further objects and the entire scope of applicabili-ty of thepresent invention wil-l become apparent from the detailed descriptiongiven hereinafter; it should be understood, however, that the detaileddescription and specific examples, while indicating preferredembodiments of the invention, are given by way of illustration only,since various changes and modifications within the spirit and scope ofthe invention will become apparent to .those skilled in the art fromthis detailed description.

lt has now been found that these objects can be attained by our improvedapparatus which spins a settable plastic composition onto the interiorysurface of a concrete pipe while the concrete is still in .the wet,green or uncured stage, evenly with uniform thickness.

In one aspect of the invention, coal tar pitch, epoxy resin and sand arepremixed and charged into a cartridge which via a conduit feeds intospin-olf means including a spinnable deep-dish element or disk. Thisassembly is lowered inside a wet, uncured concrete pipe. Material isextruded out of the cartridge onto this disk. Centrifugal force-throwsthe material against the pipe wall as the assembly is gradually raisedthrough the center of the stationary pipe. There is a fusing orintegration of the facing or barrier into the pipe itself.

The resulting product gives as good protection as vitriiied clay and isstructurally superior thereto. The conduit Patented Oct. 18, 1966 formedis not only resistant to hydrogen sulfide and sulfuric acid, but'isabrasive resistant and presents a smoother surface than conventionalconcrete which has a rough texture.

Instead of utilizing a pitch-epoxy formulation, less preferably therecan be employed an epoxy resin alone.

The apparatus according to this invention can effect a fully adhered,integrated surface-penetrating facing because of its uniqueconfiguration and operation.

The several disclosed embodiments of this invention will be bestunderstood in connecti-on with the accompanying drawings wherein:

FIGURE 1 is a view, partially in section, of one form of apparatusconstructed in accordance with the invention; f

FIGURE 2 is a view along the line 2 2 of FIGURE 1;

FIGURE 3 is a view, partially in section, of another form of apparatusconstructed in accordance with the invention;

FIGURE 4 is a sectional view along the line 4-4 of FIGURE 3;

FIGURE 5 shows a concrete pipe having a facing or barrier applied withthe apparatus of the invention and prior to curing;

FIGURE 6 is a fractional perspective view, partially broken away and insection, showing a cured concrete pipe having an integral, continuousinterior facing applied with the apparatus of the invention;

FIGURE 7 is an embodiment of t-he overall apparatus of this invention,for effecting vertical traverse of the concrete pipe by the sprayinghead with the mixture being supplied automatically;

FIGURE 8 is a detailed illustration of a portion of FIGURE 7;

FIGURE 9 is an elevational view of another embodiment of the spinningequipment, partially in cross section;

FIGURE 10 illustrates, in elevation, partially in cross section, anotherembodiment of the spinning head equipment;

FIGURE 11 illustrates another overall embodiment of the total apparatus;and

FIGURE 12 illustrates, partially and cross section, a detail `of theFIGURE 11 apparatus.

The apparatus of the present invention is particularly useful as a meansfor applying a facing composition similar to that disclosed and claimedin Whittier et al. Patent No. 2,765,288, and in accordance with themethod disclosed and claimed in our copending application Serial No.330,416, tiled December 13, 1963. Briefly, the composition may "be, forexample, a mixture of coal tar pitch and epoxy resin, along with afiller, such .as sand. According to the method in that application, thecomposition is applied to a wet uncured pipe in a way that thecomposition penetrates the interior surface of the pipe. The pipe latermay then be cured by contact with air and steam.

Referring more specifically to FIGURES 1 and 2 of the drawings there isprovided a boom 2 to which there is connected a gear box 4. The gears,such as gear 6, are driven by an air motor 8.

The boom 2 is positioned inside a wet, uncured, green, cylindricalconcrete pipe (not shown). Through the center of the boom there isprovided a conduit 10. A premixed facing composition is formed bypressure through conduit 10 into the cone 14 within the head 12 of theboom. The head 12 is connected to the drive shaft 20 by ribs 16.

By turning on the motor the entire head portion of the boom, includingcone 14, is rotated rapidly, eg., at 2000 r.p.m. The composition, as itemerges from the cone, escapes as indicated by the arrows and is brokenup and flung back when it strikes the inner wall 22 of the head.

It slowly moves up that wall then, and up over the annular plate 24. Thethus dispersed composition is then forced through the apertures in thecylindrical screen 26 which is secured to plate 24 by screws 23. Thecomposition, when it is forced through the apertures, is impinged uponand impregnates the surface of the wet, green concrete pipe to form afacing layer which becomes smooth. It was observed that there was adistortion of the pipe surface due to the force of the impingement.

The boom is gradually retracted through the pipe so that the entireinner surface receives an integral facing of uniform thickness. Thetreated pipe is placed in a steam curing chamber, air cured for 3 hoursand then put through the regular steam cure period, e.g., about 130 F.for 12 hours to cure both the concrete and the resin composition.(Alternatively, curing can be accomplished under normal atmosphericconditions in those geographic locations where high temperature andhumidity prevail, e.g., Houston, Texas.)

FIGURES 3 and 4 show another apparatus utilizing a boom 34. The facingcomposition is forced under pressure through a conduit 36 in the boom.(Instead of using a single conduit 36, it is possible to employ twoconcentric conduits with the ller, for example sand, passing through oneconduit and the balance of the composition through the other.) On theboom there is provided a gear box 38, the gears of which are driven bypulley 40 which, in turn, is connected to hydraulic motor 42.

The facing composition is forced by pressure through conduit 36 againstthe inverted V-portion 44 of the front end 46 or the head of the boom.When the motor is on, the entire forward section of the boom, includinghead 46, rotates rapidly, e.g., 2800 r.p.m., on bearings 48 and S0. Thecomposition, as it hits the V-portion 44, is broken up and dispersedtangentially along the frustoconical wall 51 of the head of the boorn inthe direction shown by the arrows, and is forced through the aperturesin the cylindrical screen 54. A. circular flange 58 extends from theouter edge or rim of the deep-dish-like head 46, i.e., from the upperend of wall 51, horizontally outward and screws S9 secure the screenthereto. The bolts 60 also secure the head 46 to a collar 62 which, inturn, is secure-d by bolts 64 to the lead portion 66 of the rotatingshaft. Each bolt 60 is surrounded by a respective spacer sleeve 67. VTheboom is retracted through the pipe in the manner previously described.

As the composition is forced through the apertures 54 by centrifugalforce, it impregnates the surface of the wet, uncured, green concretepipe, eg., a 24-inch diameter pipe, to form a facing layer. The pipe canbe cured and the resin set in the manner previously set forth.

In the specific examples described in connection with FIGURE 3, theenergy of the particles leaving the screen was 6.5 ft. lbs. per squareinch of surface.

Suicient energy must be imparted to the particles so that they strikethe concrete surface with suiiicient force to avoid air entrapment andto obtain penetration of the surface of the interior wall of theconcrete pipe.

The apparatus described in either FIGURE 1 or FIG- URE 3, has been foundadequate to impart the desired force.

As shown in FIGURE 5, the resultant green, uncured concrete pipe 68 hasa steel wire reinforcement cage 70 therein and an inner, integral,continuous facing layer 72 of pitch-epoxy resin.

FIGURE 6 shows a cured concrete pipe 74l having an interior facing layer76 of cured epoxy resin. It will be noted as stated that the facinglayer impregnates the porous surface of the concrete, is securely lockedtherein and presents an impervious, continuous surface to the contentsof the pipe, e.g., sewage containing hydrogen sulfide.

The present invention is useful in facing pipes of 4, 8, 12, 24 or 144inches internal diameter, for example, or any other desired diameter.

In the specific example the facing layer had a thickness of about 100mils. Usually, the facing layer prepared according to the invention hasa thickness of between 100 and 125 mils. However, for somel uses thethickness can be as thin as 10 mils and can be as much as 300 or 400mils or even greater.

Reference is now made to FIGURE 7, which shows one embodiment of anoverall structure for smoothly facing the uncured, green concrete pipe78. In this embodiment, the pipe is ldisposed on a platform 80 which haswheels 82 movable lalong the rails S4, in order to move the pipe 78 toand from a position in which it can be sprayed. The spinning head 86 isshown rather schematically in FIG. 7, but it may be similar to thoseshown in FIGURES 1 and 3 for example, or in accordance with spinningheads described below. As shown by the dash line 88, spinning head 86 isvertically movable from its upward solid line non-spraying position intoits dotted line position in which spraying may start. It will be notedthat in the start-spraying position, head 86 is suiciently lbelow theupper surface of platform 80 to prevent spraying of the'concrete pipeuntil the head speed and spray have reached optimum conditions. Toeffect this, the platform has a central aperture 90 around anddownwardly from which extends a spray shield 92. This shield may be ofcardboard, or of any other material, which will protect the surroundingarea from being sprayed undesirably. It is to be understood that thespraying is started while the head extends downwardly below the top ofaperture 90 so that the lower surface of the interior of the concretepipe gets sprayed as uniformly and evenly as 4the upper surfacesthereof.

In order to move the spray head up and down through the concrete pipe,the head is connected through a frame 94 t0 a cross brace 96 which hasU-shaped brackets 98 at its opposite ends for traversing the verticalstandards 100. A hydraulic cylinder or other type of motive means 102 issecured to the cross beam 104 which interconnects the standards at theirupper ends. This hydraulic cylinder has a piston 106 which extendsthrough that cross beam and connects to the frame 94, for causing thatframe and its connected spray head 86 to move vertically with thestandards 190 being the guide tracks.

As the spray head is being moved upwardly from its dotted line positionby virtue of operation of hydraulic cylinder 102 or any other meansequivalent thereto, it is necessary to force the facing composition ontothe rotating spinning disk. This is accomplished by operation of anothercylinder 168, shown in greater detail in FIGURE 8. This cylinder has apiston rod 110 which is secured through the upper open end of acomposition container 112 to a piston 114 therein, which has a rubbergasket 116 or the like surrounding its periphery for greater sealingeffect. Container 112 rests on seats 118 and may be removed therefromfor cleaning and refill purposes when piston 114 is upwardly withdrawnfrom the container. At its bottom end, container 112 has a spigot 120 towhich is detachably secured a pipe 122, which is preferably rigid, thatis positioned into the upper open end of the pipe means in t-he sprayhead, such as into the conduit 36 of FIGURE 3.

Spray head 86 in FIGURE 7 may be constructed as shown in FIGURE 9, inwhich mounting brackets 128 secure a motor 130 which has a timing typepulley 132 secured to its output shaft. This pulley cooperates with atiming gear belt 134 to rotate the similar pulley 136, which is securedto the main body 138 of the spinning head by means of bolts 149. At itsupper and lower ends, the spinning head body 138 is rotatably secured byball bearings 142 and 144, to a hub 146. This hub extends upwardly with-a threaded attachment 148, which is secured to the motor brackets 128by means of bolts 150.

At the lower end of body 138 there is secured thereto an annular plate147, with a ring 149 in between for purposes of protecting bearings andthe like from sand or the mixture sprayed from the head. Several bolts150 hold these items together. Extending downwardly from plate 147 areseveral bolts such as bolt 152 with respective spacers 154 to which areattached the main spin-off plate 156, by nuts 158. Plate 156 has ascreen 160 secured to its outer rim by cap screws 162, and includes acentral aperture 164. To the periphery of this `central aperture isattached the rim 166 of a deep-dish element 168. Concentrically of theopening formed by hub 146, is a conically shaped diverter element 170,which points upwardly and extends threadingly downward through thebottom of the deep-dish element for securement thereto by nut 172 andwasher 174.

As mentioned with regard to FIGURE 7, the composition is forced into thespray head via a rigid conduit 122. This conduit is shown in FIGURE 9 asextending into the aperture formed by hub 146, all the way down to alevel substantially below the upper surface of plate 156. As in theother spray head embodiments, it is necessary for this feed tube 122 toextend downward through aperture 164, in order for the material fedthereby to effect a creeping or like slow movement up the sides of thedeepdish to cause an even flow-out effect over rim 166 and plate 156. Inorder for this centrifugal force to effect an even and uniform spraythrough screen 160 which aids in breaking up the material into a uniformspray, it is necessary that the composition fed into the deepdish beuniformly distributed over the rim 166. This is accomplished by makingsure the material is fed into the lower portion of the deep-dish, sothat the material can only .move up the sides of the deep-dish slowly.This makes a uniform distribution of the material as it passes over rim166.

It will be noted that annular plate 147 in FIGURE 9 has a downwardextension 176 that approaches the upper side of deepdish 168 adjacentrim 166. This element 176 operates as a downward deflector of thematerial centrifugally forced against it. Accordingly, to get out, thematerial is required to come up the sides of the deep-dish through thevalve-like opening between rim 166 and deflector 176, and this assuresthe desired uniform flow-out.

The spinning head in FIGURE 9 may be employed to receive the fillermaterial or sand `separately from the composition which enters via feedtube 122. It should be understood however, that the equipment of FIGURE9 need not be employed as a mixer of the sand and resin composition, butinstead the total mixture including the sand may be introduced throughthe pipe or feed tube 122 itself. When this latter situation is thecase, the hub extension 178 need not be employed, but it is preferableto use this extension when sand is coming into the deepdish areaseparately via the bore formed by hub 146. In this way, any sand thatcomes into the area below the bott-om of hub 146 is not thrown outwardlyby centrifugal force until it is in the deep-dish mixing area.

In the FIGURES 1, 3 and 9 embodiments, it was tacitly assumed that thefiller material, eg., sand, was already in the composition at it wasforced into the upper end of the pipe or conduit of the spray head. Inanother arrangement, the filler is mixed into the cornposition in thevicinity of the spray head area, and two different spray heads of thisnature are described below.

As another embodiment of the spinning head, preferred for separatemixing of the filler material internally of the head, reference is madeto FIGURE 10. This figure illustrates the preferred embodiment of thespinning head equipment, and is quite similar to that of FIGURE 9, witha few modifications. Like parts in the two figures are given the samenumerical designation and are not particularly re-described below as toFIGURE 10. The equipment in FIGURE l0 is especially constructed for usein the apparatus of FIGURE 11, though it also may be employed in themanner referred to relative to FIG- URE 7. In FIGURE 10, a sand valvearrangement is included as is a sand control hopper. In the FIGURE l1arrangement, a sand hopper 124 is disposed on the cross beam 96 and hasa rigid sand feed conduit 126. In FIGURE 10 the sand feed conduit isdirected to a sand control hopper 186 which has a sand control valveelement 188 cooperating with the sloping side of the hub extension 148.In FIGURE 10, this valve element 188 is secured to an annular member orpipe 190 which surrounds the resin-pitch feed tube 122 for a shortdistance above the sand control hopper 186. At that point, pipe 190 hassecured to it a set-bolt arrangement 192 by which the height of valveelement 188 may be adjusted and secured.

Also in FIGURE 10, there are included over and above the FIGURE 9spinning head, a plurality of vertically extending mixing vanes 194fixed to the bottom of deep-dish element 168. These are disposed betweenthe downward hub extension 178 and feed tube 122 at points around theperiphery of the spreader boss or diverter cone 170. Each of the mixingvanes includes a vertical rod with a plurality of propellers as shown,and they may be employed as desired. They are preferable, but may beomitted. When used, they assist in mixing the sand with the resin andpitch composition.

As shown in FIGURE 11, in which parts like those in FIGURE 7 have thesame numerical designation, the spray head equipment 196 of FIGURE l0 issecured by arms 198 to frame 94 in a manner similar to that shown inFIGURE 7. The frame and spray head equipment are moved vertically bycylinder 102 and its piston 106, with standards being the guiding tracksfor respective elements 98 which are movably affixed thereto. Theembodiment shown in FIGURE 1l is particularly useful when thecomposition to be sprayed on the inner surface of a green pipe includesnot only an epoxy resin and sand, but also a coal tar pitch. Forpurposes of premixing the resin and pitch, which may be respectivelysupplied via pumps 200 and 202 through conduits 204, 206, apneumatically operated mixing chamber 208 is provided. A source of air210 is connected by conduit 212 to a pneumatic motor 214 which .rotatesthe rod 216 (FIGURE l2) and the plurality of propellers 218 attachedthereto. The mixed resin and pitch are supplied to the spinning head viathe feed tube 122 as previously indicated.

It was previously mentioned with regard to FIGURE 7 that the cart orplatform 80 had a central aperture downward from which extended acardboard or other type of protective shield 92, so that the surroundingareas would not be sprayed, due to the spray head being below theplatform surface at the start-spray position to effect a more even anduniform spray throughout the height of the pipe. A similar typeprotective shield 220 may be inserted in the top end of the concretepipe to prevent spraying the surrounding area and operators as the sprayhead exits upwardly from the pipe.

From the foregoing description of the apparatus of this invention, it isapparent that the invention provides for the object of effecting asmooth, even and uniform facing or barrier on the interior surface of agreen, uncured concrete pipe, by causing a flow-out effect through thefeature of the invention of the material being fed to the lower area ofthe deep-dish, thereby causing the material to move slowly up the sidesof the deep-dish and over the rim thereof to the annular platesurrounding the deep-dish. The centrifugal force imparted to thedeep-dish and plate, then forces the mixed composition out through ascreen to effect the required uniform spray.

Several modifications of the invention have been described, and stillfurther modifications will bec-ome apparent to those of ordinary `skillin the art upon reading this disclosure. It is intended, however, thatthis disclosure be considered illustrative, and not limitative, thescope of the invention being defined by the appended claims.

What is claimed is:

1. Equipment for centrifugally spraying material all around in a firstdirection to effect a smooth facing of such material, comprising:

spin-oit means, rotatable about a second direction axis perpendicular tosaid yfirst direction and including a concentric annular flat plate, forcausing said material to be centrifugally sprayed evenly, and generallyin said first direction, from all around the spin-oit means,

said spin-off means including a screen member disposed around an outeredge of said iat plate, said screen member extending concentrically withsaid second direction axis for aiding breakup of said material into auniform spray as the material centrifugally passes therethrough,

said spin-olf means further including a deep-dish-like elementconcentrically extending from said plate with its outer rim extending tothe edge of an aperture in said plate,

means for rotating said spin-off means rapidly so any of said materialyover said plate will be centrifugally sprayed as aforesaid with adesired impingement force on the object being faced, and

means, including pipe means extending in said second direction throughsaid plate aperture, for supplying said material into said deep-dishelement at a level substantially beyond said plate to cause the materialto be slowly moved by centrifugal force over the sides of said deep-dishelement and therefore evenly over said rim and iat plate to effect aforceful but uniform spray through said screen member.

2. Equipment for centrifugally spraying material horizontally outwardlyto effect a smooth facing of such material, comprising:

spin-off means, rotatable about a vertical axis and including aconcentric annular flat plate, for causing said material to becentrifugally sprayed evenly, and generally in a horizontal direction,from all around the spin-off means,

said spin-oli means including a vertically extending apertured memberdisposed around and upwardly from the outer edge of said flat plate foraiding breakup af said material into a uniform spray as the materialcentrifugally passes therethrough,

said spin-off means further including a deep-dish-like elementconcentrically extending below said plate with its upper rim extendingto the edge of an aperture in said plate,

means for rotating said spin-olf means rapidly so any Y of said materialover said plate will be centrifugally sprayed horizontally with desiredirnpingement force on the object being faced, and

means, including pipe means vertically extending through said plateaperture, for supplying said material into said deep-dish element at alevel substantially below the upper surface of said plate to cause thematerial to be slowly moved by centrifugal force upwardly adjacent thesides of said deep-dish element and therefore evenly over said rim andflat plate to eifect a forceful but uniform spray from said aperturedmember.

3. Equipment as in claim 2 wherein the lower end of said pipe meansflares with the bottom rim thereof being adjacent to the side walls ofsaid deep-dish-like element.

4. Equipment as in claim 2 and further including a conically shapeddiverter element disposed in the bottom of said deep-dish elementpointing upwardly and being coaxial with said pipe means to causespreading of said material as it exits therefrom.

5. Apparatus for spraying the interior of green, uncured concrete pipewith a settable plastic including an epoxy resin comprising theequipment of claim 1 along with:

means for lowering said equipment into a spray-start position and forretracting the equipment upwardly at a given speed during the sprayprocess, and

means for moving said concrete pipe into a position concentric with saidequipment and including a base plate with a central aperture throughwhich said spin-olf means downwardly extends when in its spraystartposition whereby the lower inside surface of the concrete pipe getsfully sprayed uniformly as well as the further up portions thereof.

6. Equipment as in claim 5 including mounting structure and hubstructure relatively rotatable therewith, one of said structures beingstationary with the other being coupled to drive said spin-olf means bysaid rotating means.

7. Equipment as in claim 6 wherein said hub structure is mountedinternally of said mounting structure and has a cent-ral bore which issubstantially coaxial with said vertical axis and through which saidpipe means extends.

8. Equipment as in claim 7 wherein said bore of said hub is a feed tubefor a iirst type of material and said pipe means supplies to saiddeep-dish element another type of material, which materials togethermake up the first mentioned material which is to be sprayed, therebe-ing means extending downwardly from the lower end of said lhub toextend the feed tube through said plate aperture to a level Ilower thanthe upper surface of said plate, and means adjacent the upper end ofsaid hub for regulating the amount of said first type of material to befed into said deep-dish element through said feed tube.

9. Equipment as in claim 8 wherein the upper end of said hub flaresoutwardly, said regulating means includ- -ing an element cooperativewith the liared out hub portion to regulate the fiow of said iirst typeof material by varying the size of the opening therebetween throughvertical adjustment of said regulating means.

1t). Equipment as in claim 8 and further including a deilector adjacentthe rim of said deep-dish element for preventing said material frombeing centrifugally thrown out of said deep-dish element except via saidrim.

11. 'Equipment as in claim S and further including a conically shapeddiverter element disposed at the bottom of said deep-dish element andpoint-ing upward into and coaxial with said pipe means, and a pluralityof mixing vanes extending vertically from the said bottom of saiddeep-dish element around said diverte-r element between said pipe meansand feed tube extension.

12. Apparatus for spraying the internal surface of green, uncuredconcrete pipe to effect an integral facing, comprising:

a spray station including the equipment of claim 8,

means for supplying sand through said feed tube, and

means for supplying an epoxy resin material through said pipe meansunder pressure, whereby lthe sand and resin material are mixed in thearea of said deep-dish element, so as to be centrifugally moved over therim and said ilat plate thereof and through the said screen member ontothe internal surface of said .concrete pipe while the said equipment isbeing moved upwardly through said concrete pipe.

13. Apparatus as in claim 12, for spraying a coal tar pitch and epoxyresin mastic on the internal surface of said concrete pipe, includinc':

means for supplying said coal tar pitch under pressure,

means receiving said pitch and epoxy resin for mixing same together, andmeans connecting the output mixture from that mixing means to said pipemeans for supplying the mixture to the area of said deep-dish element.

14. Equipment as in claim 13 and further including a conically shapeddiverter element disposed at the bottom of said deep-dish elementpointing upwardly concentric of said pipe means, there being a pluralityof mixing vanes spacedly disposed around said diverting element andvertically extending between sai-d pipe means and the said downward feedtube extension for mixing the sand into the said mixture as both comeinto the area of the deepdish element.

15. Apparatus as in claim 13 and further including means at the upperend of said hub for regulating the amount of sand which may be fed bysaid feed tube.

16. Apparatus as -in claim 12, including means for forcing said materialinto said pipe means as said equipment is retracted upwardly during thespraying process.

17. Equipment as in claim 2 including a deector adjacent the rim of saiddeep-dish element for prevent-ing said material from lbeingcentri'fugally thrown out of said spin-olf means except via saidapertured member.

18. Equipment for centrifugally spraying a composition materialhorizontally outwardly to elect a smooth facing of such material on theinside face of a green, uncured concrete pipe, comprising:

spin-ofr means, rotatable about a vertical axis and including aconcentric annular at plate, for causing said material to 'becentrifugally sprayed evenly, and generally in a horizontal direction,from all around the spin-o means,

sa-id spin-off means including a vertically extending screen kmemberdisposed around and upwardly from near the outer edge of said flat platefor aiding breakup of said material into a 4uniform spray as thematerial centrifugally passes therethrough,

said spin-off means furthe-r including a deep-dish-like element havingan inverted conically shaped inner surface ooncentrically extending asubstantial distance downward and inward from a central aperture in saidplate,

means for rotating said spin-off means rapidly so any of said materialover said plate will be centrifugal-ly sprayed horizontally through saidscreen member with desired impingement force on the concrete pipe beingfaced, means, including pipe means vertically extending concentricallythrough said plate aperture, for supplying said composition materialpre-mixed and centrally into said deep-dish element at a levelsubstantially below the upper surface of said plate, and

means c-ircumferentially adjacent said inner surface for preventing saidmaterial from being centrifugally thrown out of said deep-dish elementexcept by being moved by centrifugal force upwardly adjacent the sidesof sai-d deep-dish element and therefore evenly` over said flat plate toeffect a forceful but uniform spray from said screen member.

19. Equipment as in claim 18 including means for relatively moving saidspin-off means and concrete pipe vertically at least during the saidspraying of said concrete prpe.

References Cited by the Examiner UNITED STATES PATENTS 1,838,546 12/1931Halstead 25-38 2,233,855 3/19-41 suss 239-223 2,508,709 5/1950 Goetchius118-317 X 2,986,338 5/.1961 Foster 239-222 2,992,778 7/1961 Martin239-223 3,073,531 1/1963 Kothe 239-223 3,180,312 4/1965 Handley et a1.'118-317 X DANIEL BLUM, Primary Examiner,

2. EQUIPMENT FOR CENTRIFUGALLY SPRAYING MATERIAL HORIZONTALLY OUTWARDLYTO EFFECT A SMOOTH FACING OF SUCH MATERIAL, COMPRISING: SPIN-OFF MEANS,ROTATABLE ABOUT A VERTICAL AXIS AND INCLUDING A CONCENTRIC ANNULAR FLATPLATE, FOR CAUSING SAID MATERIAL TO BE CENTRIFUGALLY SPRAYED EVENLY, ANDGENERALLY IN A HORIZONTAL DIRECTION, FROM ALL AROUND THE SPIN-OFF MEANS,SAID SPIN-OFF MEANS INCLUDING A VERTICALLY EXTENDING APERTURED MEMBERDISPOSED AROUND AND UPWARDLY FROM THE OUTER EDGE OF SAID FLAT PLATE FORAIDING BREAKUP OF SAID MATERIAL INTO A UNIFORM SPRAY AS THE MATERIALCENTRIGUGALLY PASSES, THERETHROUGH, SAID SPIN-OFF MEANS FURTHEWRINCLUDING A DEEP-DISH-LIKE ELEMENT CONCENTRICALLY EXTENDING BELOW SAIDPLATE WITH ITS UPPER RIM EXTENDING TO THE EDGE OF AN APERTURE IN SAIDPLATE, MEANS FOR ROTATING SAID SPIN-OFF MEANS RAPIDLY SO ANY OF SAIDMATERIAL OVER SAID PLATE WILL BE CENTRIFUGALLY SPRAYED HORIZONTALLY WITHDESIRED IMPINGEMENT FORCE ON THE OBJECT BEING FACED, AND MEANS,INCLUDING PIPE MEANS VERTICALLY EXTENDING THROUGH SAID PLATE APERTURE,FOR SUPPLYING SAID MATERIAL INTO SAID DEEP-DISH ELEMENT AT A LEVELSUBSTANTIALLY BELOW THE UPPER SURFACE OF SAID PLATE TO CAUSE THEMATERIAL TO BE SLOWLY MOVED BY CENTRIFUGAL FORCE UPWARDLY ADJACENT THESIDES OF SAID DEEP-DISH ELEMENT AND THEREFORE EVENLY OVER SAID RIM ANDFLAT PLATE TO EFFECT A FORCEFUL BUT UNIFORM SPRAY FROM SAID APERTUREDMEMBER.